Nine-Year Trend of Anticoagulation Use, Thromboembolic Events, and Major Bleeding in Patients With Non-Valvular Atrial Fibrillation　– Shinken Database Analysis –

BACKGROUND: Trends of oral anticoagulant (OAC) prescription and incidence of thromboembolism (TE) and/or major bleeding (MB) in patients with non-valvular atrial fibrillation (NVAF) in Japan are still unclear. METHODS AND RESULTS: We used data from Shinken Database 2004-2012, which included all new patients attending the Cardiovascular Institute between June 2004 and March 2013. Of them, 2,434 patients were diagnosed with NVAF. Patients were divided into 3 time periods according to the year of initial visit: 2004-2006 (n=681), 2007-2009 (n=833), and 2010-2012 (n=920). OAC prescription rate steadily increased from 2004-2006 to 2010-2012. Between 2004-2006 and 2007-2009, irrespective of increased warfarin usage, MB tended to decrease, presumably due to low-intensity therapy and avoidance of concomitant use of dual antiplatelets, but TE did not improve. In 2010-2012, direct OACs (DOAC), preferred in low-risk patients, may have contributed to not only decrease TE, but also increase MB, especially extracranial bleeds. In high-risk patients in that time period, mostly treated with warfarin, incidence of TE and MB did not improve. CONCLUSIONS: The 9-year trend of stroke prevention indicated a steady increase of OAC prescription and a partial improvement of TE and MB. Even in the era of DOAC, TE prevention was insufficient in high-risk patients, and DOAC were associated with increased extracranial bleeding. (Circ J 2016; 80: 639-649).